OCCUPATION: Astrophysicist, author, director of the American Museum of Natural History's Hayden Planetarium and host of PBS's NOVA scienceNOW
NUMBER OF TIME COVERS: 0
PREVIOUS APPEARANCES ON THE TIME 100: 1
PRO: In a funny, genial voice, Tyson's best seller, Death By Black Hole, opened up the scientific community's understanding of the universe to the average Earthling.
CON: A black hole could open up and consume Tyson at any moment. Who's laughing now? Black holes are nothing to joke about.
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